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Odometer problem

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Old Jan 6, 2022 | 04:32 PM
  #1  
scrapheap special's Avatar
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Default Odometer problem

Hi All,
I'm in the UK and have an '99 model NB 1.8 5speed, and have noticed that the odometer is not working. The speedo and tacho work fine.
I have tried swapping a borrowed odometer unit and full clocks unit and have concluded there must be a fault with the wiring on the back of the circuit board. The car had been neglected before I bought it and the circuit board wiring looks a bit corroded (probably due to the British weather). It is not a requirement that the odometer works over here, but I need to know mileage covered for servicing etc.
Any idea which wire feeds the odometer ?

Thanks in advance.
Old Jan 7, 2022 | 10:00 AM
  #2  
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From: Toronto, Canada
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The Vehicle Speedometer Sensor is mounted on the transmission and its wires feed the cluster on pins 1M and 2M.

However, that does not help you. The odometer microcomputer drives the tachometer and speedometer which you say are both working,

The microcomputer pins, viewed on the back of the cluster from left to right are

LEFT Connector.
Tach Sin-
Tach Cos-
Tach Sin+
Tach Cos+
NC
Seat Belt (Pin 2B)
Speed Sensor (Pin 2M)
ECU (Pin 2L)
ECU (Pin 2K)
ECU (Pin 2J) - Not Connected to Vehicle
Key Reminder (Pin 3F)
Inst Light+ (Pin 3G)

RIGHT Connector.
Speedo Sin-
Speedo Cos-
Speedo Sin+
Speedo Cos+
NC
Door Switch (Pin 1L)
NC
NC
NC
Ground
12V Switched (Pin 1C)
12V Unswitched (via conditioner Out) Pin

If your fix ends up with replacing the microcomputer remember that the replacement microcomputer will retain the milage from its original vehicle.
Good Luck
Old Jan 7, 2022 | 11:39 AM
  #3  
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Check if you have constant battery voltage (aka room fuse power) as the microcomputer uses that to save the odometer value.
Old Jan 8, 2022 | 11:04 AM
  #4  
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Default

Thanks for the info everyone, I'll look into it !!
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